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Synopsis

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Acanthosis nigricans (AN) is a localized skin disorder manifesting with hyperpigmented, velvety plaques typically located in flexural and intertriginous regions. The precise pathogenesis is unknown but is speculated to involve the stimulation of insulin-like growth factor receptors and tyrosine kinase receptors on keratinocytes and fibroblasts.

II. Malignancy-associated / cutaneous paraneoplastic syndrome – Most commonly associated with gastric carcinoma, but numerous other malignancies have been reported. Elderly nonobese patients with new AN should have malignancy considered as a cause. Atypical (palmar, perioral, or mucosal) distributions or acute-onset AN may be more associated with malignancy.

III. Drug-induced – Niacin (nicotinic acid) is the most closely associated medication, but AN can also be caused by oral contraceptives, corticosteroids, diethylstilbestrol, heroin, fusidic acid, methyltestosterone, protease inhibitors, and folate.

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Drug Reaction Data

Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.